Overflows

Aquarium overflows allow water to move from your display tank down to a sump, where filtration equipment can operate out of sight. The overflow sets the display tank’s water level, and as water rises, it flows into the overflow box and drains through plumbing to the sump below. All of the overflows offered here are designed for drilled aquariums, providing a safe and reliable way to move water without relying on a touchy siphon in a hang-on-back (HOB) overflow setup.